Christoph Busch

Vocabulary

Harmonized Biometric Vocabulary

The following terms and definition are based on the ISO/IEC JTC SC37 Harmonized Biometric Vocabulary (HBV) as defined in SC37 Working Group 1 for the International Standard ISO/IEC 2382-37. The standard is freely accessible at this URL. The German and French translations are provided by the national delegates in Working Group 1 and are still subject to national body approval.

NOTE 5 Behavioural and biological characteristics cannot be completely separated which is why the definition uses ‘and’ instead of ‘and/or’. For example, a fingerprint image results from the biological characteristics of the finger ridge patterns and the behavioural act of presenting the finger.

NOTE 1 The processing algorithm may contain multiple methods, details of which may not be externally apparent. Thus a biometric system is considered as using one processing method, until it is otherwise specified.

NOTE 2 Determining what constitutes a single type of sensor, processing method or biometric characteristic will depend on convention. For example, current convention is that images of ridge patterns from both thumbs and fingers constitute a single biometric characteristic type, i.e., fingerprints. With respect to sensors, infrared and optical bandwidth sensors are considered different types, but optical bandwidth sensors are considered a single type despite imaging red, green and blue bandwidths.

NOTE 1 The application decision may include more than a comparison process. For example, a biometric capture process may show that there are no characteristics to capture and a decision can be made on this before any biometrics are compared.

NOTE 2 The subject/object labeling in a comparison might be arbitrary. In some comparisons a biometric reference might be used as the subject of the comparison with other biometric references or incoming samples used as the objects of the comparisons. For example, in a duplicate enrolment check a biometric reference will be used as the subject for comparison against all other biometric references in the database.

NOTE 2 The subject/object labeling in a comparison might be arbitrary. In some comparisons a biometric reference might be used as the subject of the comparison with other biometric references or incoming samples used as the objects of the comparisons. For example, in a duplicate enrolment check a biometric reference will be used as the subject for comparison against all other biometric references in the database.

NOTE Historically, the word match has been used as a verb to indicate the act of comparison and decision making. As ‘match’ is the decision coming out of the comparison process its use as a verb is deprecated in favour of compare.

NOTE 2 An acquisition process may produce multiple biometric samples from a single biometric capture, each biometric sample is attributable to a single biometric characteristic. For example, (1) four fingerprints in a slap image, (2) three segmented face samples of the three people in a captured photograph.

NOTE Reference adaptation may be used to improve performance (e.g. adapting the reference to take account of variability of an individual's biometric characteristics) and to mitigate performance degradation (e.g. due to changes in biometric characteristics over time).

NOTE The intent of the word "individualized" is to distinguish biometric data subjects from those whose aggregated data was used in the creation of the biometric recognition algorithm. Examples of individuals contributing biometric data who are not biometric data subjects include those who contributed to a Universal Background Model in speaker recognition systems, or who contributed to the creation of an eigenface basis set in a facial recognition system.

EXAMPLE An operator who lets unsanctioned subjects through, a user who initiates a denial of service attack, an administrator who allows unsanctioned function creep and a biometric capture subject who impersonates an enrolled user.

NOTE 2 Comparison between: identical twins; different, but related biometric characteristics from the same individual, such as left and right hand topography will need proper consideration. See ISO/IEC 19795-1.

NOTE This dictionary definition does not preclude other natural language use of the term "application" in the context of biometrics, for example, biometric samples might be collected from a biometric data subject during an application for a passport or visa.